Pressure-sensitive adhesive composition, pressure-sensitive adhesive sheet, and bonded body

Abstract

An object of the present invention is to provide a pressure-sensitive adhesive composition whose adhesive force is sufficiently reduced by applying a voltage even after storage in a high-temperature and high-humidity environment. The present invention relates to a pressure-sensitive adhesive composition containing a first polymer as a base polymer and an ionic liquid and further containing a second polymer having a glass transition temperature Tg of 40° C. to 180° C.

1 . A pressure-sensitive adhesive composition containing a first polymer as a base polymer and an ionic liquid, the pressure-sensitive adhesive composition further comprising:
 a second polymer having a glass transition temperature (Tg) of 40° C. to 180° C.   
     
     
         2 . The pressure-sensitive adhesive composition according to  claim 1 , wherein
 a difference in HSP value between the first polymer and the second polymer is 0 to 3.   
     
     
         3 . The pressure-sensitive adhesive composition according to  claim 1 , wherein
 the second polymer comprises an organic polymer compound, and a content of the organic polymer compound in the second polymer is 1 to 50 parts by mass with respect to 100 parts by mass of the first polymer.   
     
     
         4 . The pressure-sensitive adhesive composition according to  claim 1 , wherein
 an anion of the ionic liquid comprises at least one selected from the group consisting of a bis(fluorosulfonyl)imide anion and a bis(trifluoromethanesulfonyl)imide anion.   
     
     
         5 . The pressure-sensitive adhesive composition according to  claim 1 , wherein
 a cation of the ionic liquid comprises at least one selected from the group consisting of a nitrogen-containing onium cation, a sulfur-containing onium cation, and a phosphorus-containing onium cation.   
     
     
         6 . The pressure-sensitive adhesive composition according to  claim 1 , wherein
 a content of the ionic liquid is 0.5 parts by mass or more and 30 parts by mass or less with respect to 100 parts by mass of the first polymer.   
     
     
         7 . The pressure-sensitive adhesive composition according to  claim 1 , wherein
 the first polymer comprises at least one selected from the group consisting of a polyester-based polymer, a urethane-based polymer, and an acrylic polymer having a carboxyl group, an alkoxy group, a hydroxyl group and/or an amide bond.   
     
     
         8 . The pressure-sensitive adhesive composition according to  claim 1 , wherein
 the second polymer comprises a tackifying resin.   
     
     
         9 . The pressure-sensitive adhesive composition according to  claim 8 , wherein
 the tackifying resin has a softening point of 100° C. or higher.   
     
     
         10 . The pressure-sensitive adhesive composition according to  claim 8 , wherein
 a content of the tackifying resin is 1 to 50 parts by mass with respect to 100 parts by mass of the first polymer.   
     
     
         11 . The pressure-sensitive adhesive composition according to  claim 8 , wherein
 the tackifying resin is a terpene-based tackifying resin or a rosin-based tackifying resin.   
     
     
         12 . The pressure-sensitive adhesive composition according to  claim 1 , which is used for electrical debonding. 
     
     
         13 . A pressure-sensitive adhesive sheet comprising:
 a pressure-sensitive adhesive layer formed of the pressure-sensitive adhesive composition according to any one of claims  1  to  12 .   
     
     
         14 . A bonded body comprising:
 the pressure-sensitive adhesive sheet according to claim  13 ; and   a conductive material, wherein   the pressure-sensitive adhesive layer is adhered to the conductive material.